Utilization of a local exchange network by a plurality of local network operators

ABSTRACT

The invention relates to an exchange ( 1 ) for connecting telecommunications terminals ( 2   a    2   n ) of subscribers to a telecommunications network, comprising subscriber lines (TL) via which the respective telecommunications terminals ( 2   a    2   n ) are linked with the exchange ( 1 ). Said exchange ( 1 ) is operated by a first network operator and is used by further network operators. The subscriber lines (TL) and subscribers are associated with one of said network operators each and the subscribers select the exchange ( 1 ) via the telecommunications terminals ( 2   a    2   n ) to establish a telecommunications link via the respective network operator The invention further relates to a method for operating an exchange that is used in the inventive exchange ( 1 ).

[0001] The present invention relates to a switching center for connecting telecommunications terminals to a telecommunications network, as it is described in the preamble of the attached claim 1, and to a method for operating a switching center, as it is described in the preamble of the attached claim 13.

[0002] After deregulation of the telecommunications market in many countries, new network operators are constantly appearing on the market, who for the time being are acting as carriers for long-distance connections and are attempting to take traffic away from the former monopoly and from their competitors with inexpensive long-distance rates. Usually, these carriers are dialed individually (call by call) for each call, by means of a so-called carrier access code, by consumers. A prerequisite for accepting long-distance traffic is switch-through contracts between the new network operators and the network operator with whom the subscribers are physically connected, in most cases the former monopoly.

[0003] However, the new network operators are also increasingly penetrating the local sector, and are attempting to bind consumers to them with fixed contracts and lucrative conditions. These customers (subscribers) are then permanently attached to the new network operator through “preselection” in the local switching centers with which they are physically connected. For these subscribers, the new network operator generally enters into switch-through contracts with the operators of the local switching centers but leaves the actual control of functions (features) to the operators of the local switching centers.

[0004] If the new network operator wants to get to the subscriber lines directly, it must make additional arrangements with the operator of the local switching center, in some manner, in that the network operator taps the subscriber lines directly at the main distribution frame and manages a separate local switching center.

[0005] This has the disadvantage, for a new network operator, that a separate switching center in the local network sector has to be provided for the network operator's customers, and this involves a high level of investment.

[0006] The task of the present invention is therefore to provide a switching center according to the preamble of the attached claim 1, and a method used in this switching center according to the preamble of the attached claim 13, in which the use of a switching center by several network operators is made possible.

[0007] This task is accomplished by means of a switching center according to the attached claim 1, and by a method used in this switching center according to the attached claim 13.

[0008] In accordance with the present invention, a technical solution is indicated such as that achieved with modern switching centers currently in use (e.g., in the EWSD, elektronisches Wählsystem digital [electronic dialing system, digital]), so that a switching center (e.g., a local switching center) can be used by several network operators.

[0009] As a result of the assignment according to the invention of each subscriber or each subscriber connection line to one network operator, there are the following advantages both for the operator (first network operator) of the switching center and for the other network operators who use the equipment of the switching center:

[0010] The operator gains additional sources of income by selling switching center capacity and telecommunications services.

[0011] The network operators who use the capacity of a switching center of the first network operator, on the other hand, have the advantage that investment costs needed to offer telecommunications services to a subscriber in the local network sector are lower, which in turn means an earlier recovery of their investment.

[0012] Finally, customers (subscribers) have the advantage that they can select the network operator who offers them the best price and/or service.

[0013] Advantageous embodiments of the present invention are reproduced in the dependent claims, in each instance.

[0014] In one embodiment of the present invention, several switching centers are connected by way of first intermediate exchange lines. The first intermediate exchange lines or bundles of first intermediate exchange lines are also assigned to a network operator, in each instance. In this connection, each network operator can handle the telecommunications connections of its subscribers either by way of its own first intermediate exchange lines or, if the network operator has entered into appropriate switch-through agreements with other network operators, by way of the first intermediate exchange lines of the corresponding network operators.

[0015] The telecommunications connections between two subscribers are handled by way of these first intermediate exchange lines, if the subscribers are connected to different switching centers. However, if the subscribers are connected to the same switching center, the telecommunications connection can also be handled as an internal connection within the switching center.

[0016] In another embodiment of the present invention, the switching center according to the invention is connected with a switching center that acts as a so-called interconnect gateway by way of second intermediate exchange lines. The interconnect gateway has the task of bringing about the transition of a telecommunications connection from one network operator to another network operator.

[0017] However, the transition of a telecommunications connection from one network operator to another network operator can also take place within the switching center according to the invention.

[0018] According to the invention, the control of functions that relate to the telecommunications connection in each instance takes place as a function of the network operator to whom the subscriber in question is assigned in the switching center. This control takes place by means of a central control device.

[0019] The central control device controls the routing and the call rate registration (calculation of fees), for example, as a function of the network operator to whom each subscriber is assigned in the switching center.

[0020] In this connection, the central control device performs the control of the functions based on the switching center functions “origination dependent routing” and “origination dependent zoning” for call rate registration.

[0021] It is advantageous if the switching center according to the invention is administered by the first network operator. This means that an administrator has access to the central control device of the switching center, via an operating terminal, in order to set up a new subscriber for a certain network operator, for example. Administration takes place, for example, by sending administrative commands (MML commands, man-machine language) to the central control,.

[0022] Telecommunication is understood to mean both voice communication and data communication. Accordingly, subscriber lines are understood to mean, for example, lines for connecting analog terminals (a/b lines), ISDN terminals (BA, PA lines), which can be switched either as an individual connection or as a multi-device connection (e.g., private branch exchanges), terminals using the XDSL data transmission method or lines for connecting terminals using packet-oriented data transmission methods (e.g., H.323 terminals).

[0023] The present invention is explained in greater detail below using a preferred exemplary embodiment, making reference to the attached drawings, which show:

[0024]FIG. 1 The structure of the switching center according to the invention;

[0025]FIG. 2 An example of how a switching center is divided up, with identification of the network operators; and

[0026]FIG. 3 An example of message traffic between various network operators.

[0027]FIG. 1 shows an example of a switching center 1 according to the invention, which is divided up among several network operators (two, in the example).

[0028] The essential components of a switching center 1 are the subscriber connection units (also called line cards), which form the interface between the subscriber lines (TL) and the switching center, the coupling network 5, which produces the connection to the telecommunications network, and the central control 4, in which the control device according to the invention is implemented, for example as software. The telecommunications terminals 2 a . . . 2 n of the subscribers are connected with the switching center 1 by way of the subscriber lines (TL).

[0029] The individual subscribers have each entered into agreements with different network operators; i.e., the subscribers each dial into the telecommunications network by way of different network operators. In the example of FIG. 1, the subscribers 2 a and 2 b dial into the telecommunications network by way of the first network operator, and the subscriber 2 n dials in by way of the second network operator.

[0030] Control of the telecommunications connection, e.g., the routing and the call rate registration, takes place within the switching center 1 as a function of the network operator by way of which a subscriber dials in. If a subscriber dials into the telecommunications network with the terminal 2 a, for example, routing takes place by way of the telecommunications network or the lines of the first network operator or of the network operator with whom switch-through contracts for this purpose exist. Accordingly, the subscriber is billed for charges in accordance with the rate structure of the first network operator.

[0031] The advantage of the present invention is that it can be easily integrated into modern switching centers that support the functions “origination dependent routing” and “origination dependent zoning.”

[0032] Control of the functions that relate to telecommunications connections is carried out by the central control 4. Software implemented in this control recognizes the origin of a telecommunications connection (subscriber, terminal or network operator) and performs the control of the functions accordingly.

[0033] In the following, FIG. 2 is used to show an example in which the switching center 1 is divided up among four network operators.

[0034] In this example, the network operators are assigned different colors to differentiate them, and are divided up into a “red,” a “green,” a “blue” and a “yellow” network operator; this color assignment could also, for example, be used for the subscriber lines (TL) or the subscriber connection units to optically differentiate the connections to the individual terminals 2 of the individual network operators from one another.

[0035] In the example shown, each network operator has its own connection paths (lines) in the telecommunications network. If, for example, a subscriber of the “red” network operator wants to make a call, the call is generally connected by way of the lines of the “red” network operator in the telecommunications network. Likewise, in this example the calculation of fees and the connection control (call processing) take place in accordance with the rules of the “red” network operator.

[0036] These explanations apply not only to individual telecommunications terminals but also to private branch exchanges of subscribers. A switching center divided up according to the invention offers subscribers the same functionality as a conventional switching center.

[0037] According to the present invention, in the example shown, the origin markings (origination dependent routing and zoning) are used to represent the four “colors,” as a designation within the system, for the four network operators. Each of these origin markings is set by means of appropriate administrative commands in the central control, and refers to one subscriber line (TL). Every possible origin of a connection must therefore carry an origin marking.

[0038] It should be noted that dividing up a switching center according to the invention among four network operators merely represents an example; according to the invention, the switching center can be divided up among any desired number of network operators.

[0039] In the following, FIG. 3 is used to describe an example of how a telecommunications connection between two subscribers is connected.

[0040] If two subscribers of the same network operator (the “yellow” network operator, for example; one subscriber each at switching centers 1 a and 1 b) are establishing a telecommunications connection, the connection is made directly between the two switching centers 1 a and 1 b via the telecommunications network of the “yellow” network operator.

[0041] However, if a telecommunications connection is made between two subscribers of different network operators, it is advantageous if the connection is made via a so-called interconnect gateway IG. Using the example of FIG. 3, a subscriber of the “green” network operator at the switching center 1 a establishes a connection with a subscriber off the “red” network operator at the switching center 1 b. The connection then runs from the switching center 1 a via the lines of the “green” subscriber [sic] to the interconnect gateway IG. The changeover from the lines of the “green” network operator to the lines of the “red” network operator takes place in the interconnect gateway. The connection then continues via the lines of the “red” network operator to the switching center 1 b. The connection path via the interconnect gateway is therefore necessary to be able to determine precisely from which network operator the telecommunications connection is being established. Only then can handling of the connection or of the charges take place, depending on the network operator. For special telephone numbers (such as emergency telephone numbers), it is useful to issue an origin identifier that is valid for all origins. This ensures that the direct connection path is switched for connections from and to such telephone numbers.

[0042]FIG. 3 also shows the possibility that certain number ranges can be assigned to the individual network operators; for example, the number range 124/xxx is assigned to the subscribers of the “blue” network operator at the switching center 1 a. 

1. Switching center (1) for connecting telecommunications terminals (2 a . . . 2 n) of subscribers to a telecommunications network, with subscriber lines (TL), by way of which each telecommunications terminal (2 a . . . 2 n) is connected with the switching center (1), the switching center (1) being operated by a first network operator and used by other network operators, each subscriber line (TL) and each subscriber being assigned to one of these network operators, and each subscriber, to establish a telecommunications connection, dialing up the switching center (1) by way of the respective network operator assigned to them with the telecommunications terminals (2 a . . . 2 n).
 2. The switching center (1) according to claim 1, characterized by first intermediate exchange lines for connecting the switching center (1) with additional switching centers, the intermediate exchange lines being assigned to several network operators.
 3. The switching center (1) according to claim 1 or 2, characterized by second intermediate exchange lines for connecting the switching center (1) with one or more additional switching centers, which serve as a so-called interconnect gateway (IG) for the transition of a telecommunications connection from the telecommunications network of one network operator to the telecommunications network of another network operator.
 4. The switching center (1) according to claim 1 or 2, characterized in that the transition of a telecommunications connection from the telecommunications network of one network operator to the telecommunications network of another network operator takes place in the switching center (1).
 5. The switching center (1) according to claims 1 to 4, characterized by a central control device (4) for controlling functions that relate to the telecommunications connection, in each instance, depending on the network operator to whom each subscriber is assigned in the switching center (1).
 6. The switching center (1) according to claim 5, characterized in that the central control device (4) carries out routing of the telecommunications connection, depending on the network operator to whom each subscriber is assigned in the switching center (1).
 7. The switching center (1) according to claim 5 or 6, characterized in that the central control device (4) carries out the calculation of charges for the telecommunications connection, depending on the network operator to whom each subscriber is assigned in the switching center (1).
 8. The switching center (1) according to claim 5, 6 or 7, characterized in that the central control device (4) carries out control of the functions that relate to the telecommunications connection, based on the switching center functions “origination dependent routing” and “origination dependent zoning.”
 9. The switching center (1) according to one of claims 1 to 8, characterized in that the subscriber lines (TL) serve to connect analog telecommunications terminals (2 a . . . 2 n).
 10. The switching center (1) according to one of claims 1 to 8, characterized in that the subscriber lines (TL) serve to connect ISDN telecommunications terminals (2 a . . . 2 n).
 11. The switching center (1) according to one of claims 1 to 8, characterized in that the subscriber lines (TL) serve to connect telecommunications terminals (2 a . . . 2 n) for data transmission using xDSL transmission methods.
 12. The switching center (1) according to one of claims 1 to 8, characterized in that the subscriber lines (TL) serve to connect telecommunications terminals using packet-oriented transmission methods.
 13. Method for operating a switching center (1) for connecting telecommunications terminals (2 a . . . 2 n) of subscribers to a telecommunications network, with subscriber lines (TL), by way of which each telecommunications terminal (2 a . . . 2 n) is connected with the switching center (1), the switching center (1) being operated by a first network operator and used by other network operators, each subscriber line (TL) and each subscriber being assigned to one of these network operators, and the subscribers, to establish a telecommunications connection, dialing up the switching center (1) by way of the respective network operator assigned to them with the telecommunications terminals (2 a . . . 2 n).
 14. The method according to claim 13, characterized in that functions that relate to the telecommunications connection in each instance are controlled as a function of the network operator to whom each subscriber is assigned in the switching center (1).
 15. The method according to claim 14, characterized in that routing of the telecommunications connection is carried out as a function of the network operator to whom each subscriber is assigned in the switching center (1).
 16. The method according to claim 14 or 15, characterized in that the calculation of charges for the telecommunications connection is carried out as a function of the network operator to whom each subscriber is assigned in the switching center (1).
 17. The method according to claim 14, 15 or 16, characterized in that control of the functions that relate to the telecommunications connection is carried out on the basis of the switching center functions “origination dependent routing” and “origination dependent zoning.”
 18. The method according to one of claims 13 to 17, characterized in that the switching center (1) is administered by the first network operator.
 19. The method according to one of claims 13 to 18, characterized in that the transition of a telecommunications connection from the telecommunications network of one network operator to the telecommunications network of another network operator takes place in the switching center (1).
 20. The method according to one of claims 13 to 18, characterized in that the transition of a telecommunications connection from the telecommunications network of one network operator to the telecommunications network of another network operator takes place by way of an additional switching center. 